| Helena to Clarksdale (Mississippi) | 1,409.40 mi (2,268.22 km) |
| Helena to Clarkston (Georgia) | 1,698.07 mi (2,732.78 km) |
| Helena to Clarksville (Indiana) | 1,446.50 mi (2,327.91 km) |
| Helena to Clarksville (Tennessee) | 1,442.78 mi (2,321.93 km) |
| Helena to Clawson (Michigan) | 1,440.03 mi (2,317.51 km) |
| Helena to Clay (Alabama) | 1,599.85 mi (2,574.71 km) |
| Helena to Clayton (California) | 782.58 mi (1,259.45 km) |
| Helena to Clayton (Missouri) | 1,226.53 mi (1,973.91 km) |
| Helena to Clayton (North Carolina) | 1,885.40 mi (3,034.26 km) |
| Helena to Clayton (Ohio) | 1,460.53 mi (2,350.49 km) |
| Helena to Clearfield (Utah) | 379.56 mi (610.85 km) |
| Helena to Clearlake (California) | 752.49 mi (1,211.01 km) |
| Helena to Clearwater (Florida) | 2,039.04 mi (3,281.51 km) |
| Helena to Cleburne (Texas) | 1,250.55 mi (2,012.56 km) |
| Helena to Clemmons (North Carolina) | 1,781.11 mi (2,866.42 km) |
